eorex

EU1020

Feb.2009

www.eorex.com

TMRC register

Address

01H

Bit7

Bit6

Bit5

Bit4

Bit3

Bit2

Bit1

Bit0

NAME TMRC

WDT Divide

WDTEN

WDTF

TBEN

TBF

RTCEN

RTCF

Read or Write

W

W

R/W

R/W

R/W

R/W

R/W

R/W

Default Value

0

0

0

#

0

#

0

#

*TMRC.0(RTCF) : real time counter transient flag. Once TRTC signal is transient, this flag will be

set as RTCF=1 by hardware. This bit could be cleared by software.

*TMRC.1(RTCEN) : real time counter enable/disable flag.

RTCEN = 1, enable real time counter;

RTCEN = 0, disable real time counter.

*TMRC.2(TBF) : base timer transient flag. Once TBASE signal is transient, this flag will be set as

TBF=1 by hardware. This bit could be cleared by software.

*TMRC.3(TBEN) : Base timer enable/disable flag.

TBEN = 1, enable base timer;

TBEN = 0, disable base timer.

Watchdog Timer

Watchdog timer block diagram is shown as figure_B. The clock source comes from CPU system clock.

Figure_B

Note:

*Once TMRC.5 (WDTEN) is set as “1”, the watchdog timer will start to count till the watchdog timer

overflows, and then the TMRC.4 (WDTF) is set as “1”. Meanwhile, CPU will have a warm reset by

hardware and the data in addresses $2FFCH and $2FFDH will be loaded into program counter.

Watchdog timer can be cleared by setting TMRC.5 (WDTEN=0). Please note well that the

EU1020 watchdog timer is preset as disable after power on reset. Once watchdog timer is

enabled by setting TMRC.5=1, watchdog timer won’t be stopped by software. Set

TMRC.5=0 will just clear watchdog timer counter.

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